Protective effects of dietary fibre against manganese-induced neurobehavioral aberrations in rats

We tested the hypothesis that dietary fi bre (DF) has protective effects against manganese (Mn)-induced neurotoxicity. Forty-eight one-month old Sprague-Dawley rats were randomly divided into six groups: control, 16 % DF, Mn (50 mg kg-1 body weight), Mn+ 4 % DF, Mn+ 8 % DF, and Mn+ 16 % DF. After oral administration of Mn (as MnCl2) by intragastric tube during one month, we determined Mn concentrations in the blood, liver, cerebral cortex, and stool and tested neurobehavioral functions. Administration of Mn was associated with increased Mn concentration in the blood, liver, and cerebral cortex and increased Mn excretion in the stool. Aberrations in neurobehavioral performance included increases in escape latency and number of errors and decrease in step-down latency. Irrespective of the applied dose, the addition of DF in forage decreased tissue Mn concentrations and increased Mn excretion rate in the stool by 20 % to 35 %. All neurobehavioral aberrations were also improved. Our fi ndings show that oral exposure to Mn may cause neurobehavioral abnormalities in adult rats that could be effi ciently alleviated by concomitant supplementation of DF in animal feed.

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Cerebral cortex does not modulate “regulated” decrease in core temperature during hypoxemia in rats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1998.274.4.r1158 ◽

1998 ◽

Vol 274 (4) ◽

pp. R1158-R1161

Author(s):

Evvi-Lynn M. Rollins ◽

James E. Fewell

Keyword(s):

Cerebral Cortex ◽

Core Temperature ◽

Cortical Spreading Depression ◽

Spreading Depression ◽

Temperature Response ◽

Sprague Dawley ◽

Adult Rats ◽

The Core ◽

Sprague Dawley Rats ◽

Before And After

In newborns and adults of a number of species including humans, exposure to acute hypoxemia produces a “regulated” decease in core temperature, the mechanism of which is unknown. Considering that various cortical areas participate in autonomic regulation including thermoregulation, the present experiments were carried out to test the hypothesis that the cerebral cortex plays a role in modulating the regulated decrease in core temperature during acute hypoxemia. This hypothesis was tested by determining the core temperature response to acute hypoxemia in chronically instrumented adult Sprague-Dawley rats before and after cortical spreading depression (i.e., functional decortication) was produced by the local application of potassium chloride to the dura overlying the cerebral hemispheres. There was no effect of cortical spreading depression on baseline core temperature. Core temperature decreased during acute hypoxemia in a similar fashion when the cerebral cortex was intact as well as during functional decortication. Thus our data do not support the hypothesis that the cerebral cortex modulates the regulated decrease in core temperature that occurs in adult rats during acute hypoxemia.

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Effects of estrogen on cerebrovascular function: age-dependent shifts from beneficial to detrimental in small cerebral arteries of the rat

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00645.2015 ◽

2016 ◽

Vol 310 (10) ◽

pp. H1285-H1294 ◽

Cited By ~ 10

Author(s):

Rachel R. Deer ◽

John N. Stallone

Keyword(s):

Cerebral Arteries ◽

Protective Effects ◽

Estrogen Replacement ◽

Sprague Dawley ◽

Vascular Effects ◽

Adult Rats ◽

Exogenous Estrogen ◽

Cerebrovascular Function ◽

Sprague Dawley Rats ◽

Age Dependent

In the present study, interactions of age and estrogen in the modulation of cerebrovascular function were examined in small arteries <150 μM. The hypothesis tested was that age enhances deleterious effects of exogenous estrogen by augmenting constrictor prostanoid (CP)-potentiated reactivity of the female (F) cerebrovasculature. F Sprague-Dawley rats approximating key stages of “hormonal aging” in humans were studied: perimenopausal (mature multi-gravid, MA, cyclic, 5–6 mo of age) and postmenopausal (reproductively senescent, RS, acyclic 10–12 mo of age). Rats underwent bilateral ovariectomy and were given estrogen replacement therapy (E) or placebo (O) for 14–21 days. Vasopressin reactivity (VP, 10−12–10−7 M) was measured in pressurized middle cerebral artery segments, alone or in the presence of COX-1- (SC560, 1 μM) or COX-2- (NS398, 10 μM) selective inhibitors. VP-stimulated release of prostacyclin (PGI2) and thromboxane (TXA2) were assessed by radioimmunoassay of 6-keto-PGF1α and TXB2 (stable metabolites). VP-induced vasoconstriction was attenuated in ovariectomized + estrogen-replaced, multigravid adult rats (5–6 mo; MAE) but potentiated in older ovariectomized + estrogen-replaced, reproductively senescent rats (12–14 mo; RSE). SC560 and NS398 reduced reactivity similarly in ovariectomized multigravid adult rats (5–6 mo; MAO) and ovariectomized reproductively senescent rat (12–14 mo; RSO). In MAE, reactivity to VP was reduced to a greater extent by SC560 than by NS398; however, in RSE, this effect was reversed. VP-stimulated PGI2 was increased by estrogen, yet reduced by age. VP-stimulated TXA2 was increased by estrogen and age in RSE but did not differ in MAO and RSO. Taken together, these data reveal that the vascular effects of estrogen are distinctly age-dependent in F rats. In younger MA, beneficial and protective effects of estrogen are evident (decreased vasoconstriction, increased dilator prostanoid function). Conversely, in older RS, detrimental effects of estrogen begin to be manifested (enhanced vasoconstriction and CP function). These findings may lead to age-specific estrogen replacement therapies that maximize beneficial and minimize detrimental effects of this hormone on small cerebral arteries that regulate blood flow. Listen to this article's corresponding podcast at http://ajpheart.podbean.com/e/effects-of-age-and-estrogen-on-cerebrovascular-function/ .

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Prepubertal Exposure to Genistein Alleviates Di-(2-ethylhexyl) Phthalate Induced Testicular Oxidative Stress in Adult Rats

BioMed Research International ◽

10.1155/2014/598630 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 7

Author(s):

Lian-Dong Zhang ◽

He-Cheng Li ◽

Tie Chong ◽

Ming Gao ◽

Jian Yin ◽

...

Keyword(s):

Oxidative Stress ◽

Body Weight ◽

Protective Effects ◽

Sprague Dawley ◽

Adult Rats ◽

Environmental Endocrine Disruptors ◽

Sprague Dawley Rats ◽

Antioxidative Effects ◽

Testicular Histology ◽

Ethylhexyl Phthalate

Di-(2-ethylhexyl) phthalate (DEHP) is the most widely used plastizer in the world and can suppress testosterone production via activation of oxidative stress. Genistein (GEN) is one of the isoflavones ingredients exhibiting weak estrogenic and potentially antioxidative effects. However, study on reproductive effects following prepubertal multiple endocrine disrupters exposure has been lacking. In this study, DEHP and GEN were administrated to prepubertal male Sprague-Dawley rats by gavage from postnatal day 22 (PND22) to PND35 with vehicle control, GEN at 50 mg/kg body weight (bw)/day (G), DEHP at 50, 150, 450 mg/kg bw/day (D50, D150, D450) and their mixture (G + D50, G + D150, G + D450). On PND90, general morphometry (body weight, AGD, organ weight, and organ coefficient), testicular redox state, and testicular histology were studied. Our results indicated that DEHP could significantly decrease sex organs weight, organ coefficient, and testicular antioxidative ability, which largely depended on the dose of DEHP. However, coadministration of GEN could partially alleviate DEHP-induced reproductive injuries via enhancement of testicular antioxidative enzymes activities, which indicates that GEN has protective effects on DEHP-induced male reproductive system damage after prepubertal exposure and GEN may have promising future in its curative antioxidative role for reproductive disorders caused by other environmental endocrine disruptors.

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Evaluation of Reproductive Development Following Intravenous and Oral Exposure to DEHP in Male Neonatal Rats

International Journal of Toxicology ◽

10.1080/10915810305098 ◽

2003 ◽

Vol 22 (3) ◽

pp. 159-174 ◽

Cited By ~ 26

Author(s):

Jon N. Cammack ◽

Randy D. White ◽

Donovan Gordon ◽

Jerome Gass ◽

Lawrence Hecker ◽

...

Keyword(s):

Sperm Count ◽

Liver Weight ◽

Oral Exposure ◽

Seminiferous Tubules ◽

Primary Group ◽

Sprague Dawley ◽

Intravenous Injections ◽

Sprague Dawley Rats ◽

Recovery Group ◽

Ethylhexyl Phthalate

Di-(2-ethylhexyl)phthalate (DEHP) was administered to 3- to 5-day-old male Sprague-Dawley rats by daily intravenous injections of 60, 300, or 600 mg/kg/day or by daily oral gavage of 300 or 600 mg/kg/day for 21 days. Histopathological evaluation and organ weight measurements were performed on some animals after 21 days of dosing (primary group) and later on the recovery group animals that were held without further treatment until sexual maturity at approximately 90 days of age. No effects of any type were observed in animals treated intravenously with 60 mg/kg/day. Testicular changes, consisting of a partial depletion of the germinal epithelium and/or decrease in diameter of seminiferous tubules, were present in all animals of the 300- and 600-mg/kg/day groups after the 21-day dosing period. Testes weight decreased and liver weight increased in these animals. Testes changes were dose-related and generally more severe among animals dosed orally versus intravenously. In the recovery animals, a residual DEHP-induced decrease in seminiferous tubule diameter was present in the testis of several animals dosed orally at 300 and 600 mg/kg/day, but not in animals dosed intravenously. There was no germinal cell depletion or Sertoli cell alteration observed in any dose group at any time. Notably, no effects on sperm count, sperm morphology, or sperm motility were observed at 90 days of age in any of the groups.

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Short-Term High Fat Intake Does Not Significantly Alter Markers of Renal Function or Inflammation in Young Male Sprague-Dawley Rats

Journal of Nutrition and Metabolism ◽

10.1155/2015/157520 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Catherine Crinigan ◽

Matthew Calhoun ◽

Karen L. Sweazea

Keyword(s):

Kidney Disease ◽

Renal Mass ◽

Early Stage ◽

Young Male ◽

Protective Effects ◽

Sprague Dawley ◽

High Fat ◽

Short Term ◽

Sprague Dawley Rats ◽

The Impact

Chronic high fat feeding is correlated with diabetes and kidney disease. However, the impact of short-term high fat diets (HFD) is not well-understood. Six weeks of HFD result in indices of metabolic syndrome (increased adiposity, hyperglycemia, hyperinsulinemia, hyperlipidemia, hyperleptinemia, and impaired endothelium-dependent vasodilation) compared to rats fed on standard chow. The hypothesis was that short-term HFD would induce early signs of renal disease. Young male Sprague-Dawley rats were fed either HFD (60% fat) or standard chow (5% fat) for six weeks. Morphology was determined by measuring changes in renal mass and microstructure. Kidney function was measured by analyzing urinary protein, creatinine, and hydrogen peroxide (H2O2) concentrations, as well as plasma cystatin C concentrations. Renal damage was measured through assessment of urinary oxDNA/RNA concentrations as well as renal lipid peroxidation, tumor necrosis factor alpha (TNFα), and interleukin 6 (IL-6). Despite HFD significantly increasing adiposity and renal mass, there was no evidence of early stage kidney disease as measured by changes in urinary and plasma biomarkers as well as histology. These findings suggest that moderate hyperglycemia and inflammation produced by short-term HFD are not sufficient to damage kidneys or that the ketogenic HFD may have protective effects within the kidneys.

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Effects of ovariectomy and estrogen on ischemia-reperfusion injury in hindlimbs of female rats

Journal of Applied Physiology ◽

10.1152/jappl.2001.91.4.1828 ◽

2001 ◽

Vol 91 (4) ◽

pp. 1828-1835 ◽

Cited By ~ 60

Author(s):

Nicole Stupka ◽

Peter M. Tiidus

Keyword(s):

Muscle Damage ◽

Ischemia Reperfusion Injury ◽

Serum Insulin ◽

Ischemia Reperfusion ◽

Neutrophil Infiltration ◽

Female Rats ◽

Protective Effects ◽

Sprague Dawley ◽

Sprague Dawley Rats ◽

17Β Estradiol

The effects of estrogen and ovariectomy on indexes of muscle damage after 2 h of complete hindlimb ischemia and 2 h of reperfusion were investigated in female Sprague-Dawley rats. The rats were assigned to one of three experimental groups: ovariectomized with a 17β-estradiol pellet implant (OE), ovariectomized with a placebo pellet implant (OP), or control with intact ovaries (R). It was hypothesized that following ischemia-reperfusion (I/R), muscle damage indexes [serum creatine kinase (CK) activity, calpain-like activity, inflammatory cell infiltration, and markers of lipid peroxidation (thiobarbituric-reactive substances)] would be lower in the OE and R rats compared with the OP rats due to the protective effects of estrogen. Serum CK activity following I/R was greater ( P < 0.01) in the R rats vs. OP rats and similar in the OP and OE rats. Calpain-like activity was greatest in the R rats ( P < 0.01) and similar in the OP and OE rats. Neutrophil infiltration was assessed using the myeloperoxidase (MPO) assay and immunohistochemical staining for CD43-positive (CD43+) cells. MPO activity was lower ( P < 0.05) in the OE rats compared with any other group and similar in the OP and R rats. The number of CD43+ cells was greater ( P < 0.01) in the OP rats compared with the OE and R rats and similar in the OE and R rats. The OE rats had lower ( P < 0.05) thiobarbituric-reactive substance content following I/R compared with the R and OP rats. Indexes of muscle damage were consistently attenuated in the OE rats but not in the R rats. A 10-fold difference in serum estrogen content may mediate this. Surprisingly, serum CK activity and muscle calpain-like activity were lower ( P< 0.05) in the OP rats compared with the R rats. Increases in serum insulin-like growth factor-1 content ( P < 0.05) due to ovariectomy were hypothesized to account for this finding. Thus both ovariectomy and estrogen supplementation have differential effects on indexes of I/R muscle damage.

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Effects of adolescent caffeine consumption on cocaine self-administration and reinstatement of cocaine seeking

Journal of Psychopharmacology ◽

10.1177/0269881118812098 ◽

2018 ◽

Vol 33 (1) ◽

pp. 132-144

Author(s):

Tracey A Larson ◽

Casey E O’Neill ◽

Michaela P Palumbo ◽

Ryan K Bachtell

Keyword(s):

Dose Response ◽

Extinction Training ◽

Schedules Of Reinforcement ◽

Sprague Dawley ◽

Self Administration ◽

Caffeine Consumption ◽

Adult Rats ◽

Sprague Dawley Rats ◽

Cocaine Seeking ◽

Administration Procedure

Background: Caffeine consumption by children and adolescents has risen dramatically in recent years, yet the lasting effects of caffeine consumption during adolescence remain poorly understood. Aim: These experiments explore the effects of adolescent caffeine consumption on cocaine self-administration and seeking using a rodent model. Methods: Sprague-Dawley rats consumed caffeine for 28 days during the adolescent period. Following the caffeine consumption period, the caffeine solution was replaced with water for the remainder of the experiment. Age-matched control rats received water for the duration of the study. Behavioral testing in a cocaine self-administration procedure occurred during adulthood (postnatal days 62–82) to evaluate how adolescent caffeine exposure influenced the reinforcing properties of cocaine. Cocaine seeking was also tested during extinction training and reinstatement tests following cocaine self-administration. Results: Adolescent caffeine consumption increased the acquisition of cocaine self-administration and increased performance on different schedules of reinforcement. Consumption of caffeine in adult rats did not produce similar enhancements in cocaine self-administration. Adolescent caffeine consumption also produced an upward shift in the U-shaped dose response curve on cocaine self-administration maintained on a within-session dose-response procedure. Adolescent caffeine consumption had no effect on cocaine seeking during extinction training or reinstatement of cocaine seeking by cues or cocaine. Conclusions: These findings suggest that caffeine consumption during adolescence may enhance the reinforcing properties of cocaine, leading to enhanced acquisition that may contribute to increased addiction vulnerability.

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Enteral Baicalin, a Flavone Glycoside, Reduces Indicators of Cardiac Surgery-Associated Acute Kidney Injury in Rats

Cardiorenal Medicine ◽

10.1159/000492159 ◽

2018 ◽

Vol 9 (1) ◽

pp. 31-40 ◽

Cited By ~ 3

Author(s):

Jing Shi ◽

Guofeng Wu ◽

Xiaohua Zou ◽

Ke Jiang

Keyword(s):

Oxidative Stress ◽

Acute Kidney Injury ◽

Cardiac Surgery ◽

Kidney Injury ◽

Renal Tissue ◽

Myeloperoxidase Activity ◽

Protective Effects ◽

Sprague Dawley ◽

Injury Index ◽

Sprague Dawley Rats

Background/Aims: Cardiac surgery-associated acute kidney injury (CSA-AKI) is one of the most common postoperative complications in intensive care medicine. Baicalin has been shown to have anti-inflammatory and antioxidant roles in various disorders. We aimed to test the protective effects of baicalin on CSA-AKI using a rat model. Methods: Sprague-Dawley rats underwent 75 min of cardiopulmonary bypass (CPB) with 45 min of cardioplegic arrest (CA) to establish the AKI model. Baicalin was administered at different doses intragastrically 1 h before CPB. The control and treated rats were subjected to the evaluation of different kidney injury index and inflammation biomarkers. Results: Baicalin significantly attenuated CPB/CA-induced AKI in rats, as evidenced by the lower levels of serum creatinine, serum NGAL, and Kim1. Baicalin remarkably inhibited oxidative stress, reflected in the decreased malondialdehyde and myeloperoxidase activity, and enhanced superoxide dismutase activity and glutathione in renal tissue. Baicalin suppressed the expression of IL-18 and iNOS, and activated the Nrf2/HO-1 pathway. Conclusion: Our data indicated that baicalin mediated CPB/CA-induced AKI by decreasing the oxidative stress and inflammation in the renal tissues, and that baicalin possesses the potential to be developed as a therapeutic tool in clinical use for CSA-AKI.

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Effect of a Lower Limb Restless Period on Expression of Mir-1 and Mir-206 Neural Muscle Genes in Endurance Training Rats

Journal of Arak University of Medical Sciences ◽

10.32598/jams.23.4.5947.1 ◽

2020 ◽

Vol 23 (4) ◽

pp. 570-579

Author(s):

Mahboubeh Sheikhan ◽

◽

Mohammad Reza Kordi ◽

Hamid Rajabi ◽

◽

...

Keyword(s):

Muscular Atrophy ◽

Control Group ◽

Protective Effects ◽

Sprague Dawley ◽

Medical Sciences ◽

Sprague Dawley Rats ◽

Muscle Genes ◽

Univariate Anova ◽

Pcr Method ◽

Post Hoc

Background and Aim: Several microRNAs are involved in regulating muscle mass, which plays an essential role in hypertrophy and atrophy of skeletal muscle, The present study examined the expression of some genes as regulators of muscular atrophy following a period of inertia in rats. Methods & Materials: For this purpose, 18 male Sprague-Dawley rats were divided into three groups (Control, Exercise+inactivity, and Inactivity). The exercise+inactivity group run on the treadmill for 18 weeks and five times per week. The hindlimb of the animal was immobilized for seven days with the casting method. Soleus muscle was extracted and the expression of the genes was measured by the RT-PCR method. Univariate ANOVA and Tukey post hoc test was used to determine the differences (α=0.05). Ethical Considerations: The Ethics Committee of the Tehran University of Medical Sciences Research approved this study (Code: IR.SUMS.REC.1396.S 463). Results: Results showed that immobilization in both Exercise+ inactivity and inactivity groups, compare to the control group, increased expression of miR-1 genes (P<0.10), FOXO3a (P<0.001) and decreased expression of miR-206 (P<0.007) and IGF-1 (P<0.001). This difference was statistically significant. Conclusion: According to the results of this study, it can be said that changes in the expression of RNAs by chromatography cause changes in the expression of muscle regulating genes, and although endurance exercises have protective effects, they cannot prevent these changes.

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